Log request and exceptions for handlers that use escapeHttp and terminateConnection #94
Description
When using escapeHttp or terminateConnection to serve a request, the Snap HTTP server will not make any attempt to log the request, or any exception that the handler may throw.
I would prefer if Snap logs the requested path and any exception that the handler might throw. I found this useful in my Threepenny-GUI project. See also HeinrichApfelmus/threepenny-gui#145 .
Here is a minimal complete test case for the reported behavior:
$ cat SnapTest.hs
{-# LANGUAGE OverloadedStrings #-}
import qualified Data.ByteString.Char8 as BS (hPutStrLn)
import qualified Control.Exception as E
import Snap.Core as Snap
import qualified Snap.Http.Server as Snap
import System.IO (stderr)
config = Snap.setErrorLog (Snap.ConfigIoLog $ BS.hPutStrLn stderr)
$ Snap.setAccessLog (Snap.ConfigIoLog $ BS.hPutStrLn stderr)
$ Snap.defaultConfig
main = Snap.httpServe config $ route
[ ("escape" , Snap.escapeHttp $ \_ _ _ -> E.throw msg)
, ("terminate", Snap.terminateConnection msg)]
msg = E.AssertionFailed "Hello?"
Request issued
$ curl http://0.0.0.0:8000
<!DOCTYPE html>
<html>
<head>
<title>Not found</title>
</head>
<body>
<code>No handler accepted "/"</code>
</body></html>
$ curl http://0.0.0.0:8000/escape
curl: (52) Empty reply from server
$ curl http://0.0.0.0:8000/terminate
curl: (52) Empty reply from server
and the corresponding log
$ runhaskell SnapTest.hs
no port specified, defaulting to port 8000
Listening on http://0.0.0.0:8000
127.0.0.1 - - [07/Dec/2016:23:04:54 +0100] "GET / HTTP/1.1" 404 198 - "curl/7.30.0"
The second and third request have not generated any log entry.